The interactive MLAB mathematical modeling language will be available shortly from Civilized software in a convenient version for personal computers. This version allows the ready graphical on-screen display of input data and of results from scientific computation. Graphs so constructed may also be converted to a disk file for transmission to a Postscript laser printer, allowing inclusion in scientific articles. Such screen and hardcopy visualization, often vitally facilitating to the research task, is initially limited to two-dimensional graphics. This proposal seeks to add three-dimensional graphics capabilities, thus allowing visualization of 3-parameter systems, including real-world objects of biomedical interest. Phase I will concentrate on the basic functionality for positioning and drawing surfaces in a perspective rendering of three-space. A modest but useful choice of surface rendering styles will be initially provided. An important component of this effort is selection and implementation of a hidden-surface algorithm. The scientist will see this functionality as two new MLAB commands, that allow manipulation of the viewing angle and the portrayal style of surfaces, planes, and coordinates. Design work will situate these command as part of a richer Phase II command set, with extended graphical visualization and manipulation abilities.